In an unusual move, Apple on Thursday released a second gold master of macOS Sierra to developers, even though the final release of the OS is just five days away.
The new GM build is 16A323, versus the first's 16A320 designation. The latter was released eight days ago alongside GMs for iOS 10, watchOS 3, and tvOS 10, all three of which are now officially available.
Typically software creators release just a single GM, as it's meant to represent finished code. In some cases, though, Apple and other companies may spot bugs at the last minute that are critical enough to correct as soon as possible.
Sierra will be a free upgrade for Mac owners, and introduce Siri and Apple Pay to the platform for the first time. The OS will contain a number of other features as well, such as an enhanced Photos app, a Universal Clipboard, and deeper iCloud Drive integration into the file system.